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Virtual Cement and Concrete Testing Laboratory


The Virtual Cement and Concrete Testing Laboratory (VCCTL) project develops and integrates state-of-the-art computational materials science tools into a user friendly software interface that can be used by industry to expedite the development, testing, and quality control of cement and concrete materials.  The simulation programs and software interface are being developed by NIST within a consortium of industry partners.


The intended impact of this project is to enable a rapid and convenient virtual computing environment for evaluating and optimizing cementitious materials. Substantial savings in time, materials (purchase and disposal), human resources, and money can be achieved by reducing the number of physical tests performed on concrete by private industry.

In January 2000, a NIST-led industry consortium was formed to develop a Virtual Cement and Concrete Testing Laboratory (VCCTL). VCCTL is led by the Materials and Construction Research Division within the Engineering Laboratory, along with the High-Performance Computing and Visualization Group in NIST's Information Technology Laboratory (ITL). The core of the virtual lab is a computer model for the simulating the hydration and microstructure development of cement-based materials that is based on 15 years of research at NIST. Much of this research is described in an electronic monograph available at

Now entering its 13th year, the VCCTL consortium continues to conduct computational research and experimental validation to improve the predictive ability of the software. This research leads to enhancements and additions to the base models and user interface, based on the specific interests of the consortium members.

The purpose of VCCTL software is to provide a platform for a virtual testing laboratory that can be used by concrete scientists, engineers, and technologists to explore the properties of cement paste and concrete materials. With this software, the user can
  • create virtual materials, using carefully characterized cement powders, supplementary cementitious materials, fillers, and aggregates
  • simulate the curing of these materials under a wide range of conditions
  • calculate and analyze the thermal, mechanical, and transport properties of the materials as a function of the curing conditions

For details about how to join the VCCTL consortium, please contact jeffrey.bullard [at] (Jeff Bullard).

Major Accomplishments

  • DOC Silver Medal: The success of the VCCTL Consortium activities was recognized by  a 2009 U.S. Department of Commerce Silver Medal Award for "creating the unprecedented capability to predict the performance of concrete—the key material used in the U.S. physical infrastructure."
  • Publication Awards: The following awards have been received by technical publications based on VCCTL research:
    • J.W. Bullard, A determination of hydration mechanisms for tricalcium silicate using a kinetic cellular automaton model, J. Am. Ceram. Soc. 91 (2007) 2088-2097, received the 2008 Communication Award from NIST's Building and Fire Research Laboratory.
    • J.W. Bullard and R.J. Flatt, New insights into the effect of calcium hydroxide precipitation on the kinetics of tricalcium silicate hydration, J. Am. Ceram. Soc. 93 (2010) 1894-1903, received the 2010 Communication Award from NIST's Engineering Laboratory and the 2011 Stephen Brunauer Award from the American Ceramic Society.

eVCCTL Software

A modified version of the VCCTL software, suitable for educational uses, has been developed and is now available for download. eVCCTL is a standalone application that runs on desktop or laptop computers and can be downloaded as a single executable installer.

Please visit the eVCCTL page for more information and to access the software.

Created December 6, 2010, Updated November 1, 2019